The Green River Formation, a largely vacant area where Colorado, Utah, and Wyoming come together, contains about as much recoverable oil as all the rest the world's proven reserves combined, the Government Accountability Office reports.

Most of the oil is beneath federal land overseen by the Department of the Interior's Bureau of Land Management, but the government has "locked up" development of the huge resource, critics charge.

Anu K. Mittal, the GAO's director of natural resources and environment, said in written testimony submitted to the House Subcommittee on Energy and Environment: "The Green River Formation — an assemblage of over 1,000 feet of sedimentary rocks that lie beneath parts of Colorado, Utah, and Wyoming — contains the world's largest deposits of oil shale.

"USGS [U.S. Geological Survey] estimates that the Green River Formation contains about 3 trillion barrels of oil, and about half of this may be recoverable, depending on available technology and economic conditions.

"The Rand Corporation, a nonprofit research organization, estimates that 30 to 60 percent of the oil shale in the Green River Formation can be recovered. At the midpoint of this estimate, almost half of the 3 trillion barrels of oil would be recoverable. This is an amount about equal to the entire world's proven oil reserves."

For purposes of comparison, the entire Middle East is estimated to have less than 700 billion barrels of proven reserves.

Mittal also stated: "Being able to tap this vast amount of oil locked within this formation will go a long way to help to meet our future demands for oil.

"As you can imagine, having the technology to develop this vast energy resource will lead to a number of important socioeconomic benefits including the creation of jobs, increases in wealth, and increases in tax and royalty payments for federal and state governments."

She added that the federal government therefore is in "a unique position to influence the development of oil shale," according to GAO testimony.

But in testimony that the Obama administration could seize upon to rebuff calls for development of the oil shale, which environmentalists generally oppose, Mittal also noted: "While large-scale oil-shale development offers socioeconomic opportunities, it also poses certain socioeconomic challenges that also should not be overlooked.

"Oil shale development like other extractive industries can bring a sizable influx of workers who along with their families put additional stresses on local infrastructure.

"Developing oil shale and providing power for oil shale operations and other activities will require large amounts of water and could have significant impacts on the quality and quantity of surface and groundwater resources.

"Oil shale operations will also require the clearing of large surface areas of topsoil and vegetation which can affect wildlife habitat, and the withdrawal of large quantities of surface water which could also negatively impact aquatic life."

However, Investor's Business Daily observes that the GAO testimony is "exploding the Big Lie pushed by President Obama that we can't drill our way out of high gas prices because we have but 2 percent of the world's proven oil reserves.

"Just one small part of the U.S. is capable of outproducing the rest of the planet.

"Given that current U.S. daily oil consumption is running at 19.5 million barrels, the staggering amount of Green River reserves would by itself supply domestic oil consumption for more than 200 years.

Former President Bill Clinton is abandoning his longtime political ally Charles Rangel, who is facing a difficult re-election challenge following redistricting in New York State.

Rangel, 81, has been in office since 1971, but his new district is 57 percent Hispanic and just 27 percent African-American. He is being challenged in the Democratic primary by state Sen. Adriano Espaillat and former Clinton aide Clyde Williams.

Williams was a domestic policy adviser in the Clinton administration and also served as a top aide at the Clinton Foundation.

Clinton "is grateful for Clyde's work with the foundation," a Clinton official told the New York Post.

"Because he has personal relationships with several of the candidates in the race, he doesn't feel it's appropriate to weigh in on the race."

Clinton strongly endorsed Rangel's re-election in 2010 when the longtime incumbent was facing House ethics violations that later led to a congressional censure. Clinton even taped a message to voters on Rangel's behalf, according to the Post.

Rangel for his part strongly defended Clinton during his impeachment ordeal and helped Hillary Clinton get elected to the Senate from New York.

He also backed Hillary against primary rival Barack Obama in 2008. Like Bill Clinton, Obama is staying neutral in this year's primary.

By 2015, the United States will face a shortfall of nearly 30,000 primary care physicians, due largely to Obamacare — and a shortage of 65,800 by 2025, the Association of American Medical Colleges predicts.

The shortfall is attributable in part to deterrents to entering the field, such as relatively lower incomes compared to specialists, and the growth of the elderly population in America.

But the biggest culprit would be Obamacare. If the healthcare reform bill is not overturned by the Supreme Court, up to 33 million previously uninsured Americans will be covered by health insurance, leading to a sharp increase in the demand for medical services. And even if Obamacare is not fully implemented and merely expands Medicaid coverage, 17 million Americans will be added to the Medicaid rolls by 2020.

There is, however, a readily available solution for reducing the demand for primary care physicians, according to Dr. John Rowe, professor in the department of health policy and management at the Columbia University Mailman School of Public Health.

"One of the best ways to alleviate this shortage is to expand the scope of practice for advanced practice registered nurses (APRNs), well-trained registered nurses with specialized qualifications who can make diagnoses, order tests and referrals, and write prescriptions," he writes in The Atlantic.

"APRNs could provide a variety of services that primary care physicians now provide."

He cites a report from the Institute of Medicine of the National Academy of Sciences that found that properly trained APRNs can provide core primary care services as effectively as physicians.

But Rowe points to a problem: Nurses are permitted to practice "independently to the full extent of their training and competence" in only 16 states and the District of Columbia, while the other states impose regulations limiting their practice.

And the American Medical Association, the American Academy of Family Physicians, and several other professional organizations oppose expanded use of APRNs, despite recent research showing that such use would have "no impact on primary care physician income," observes Rowe, who was previously president of the Mount Sinai Hospital and Mount Sinai School of Medicine in New York City.

He adds that nurses can be trained faster and at a much lower cost than doctors, and declares: "Tapping nursing's potential is the fastest and least expensive way to meet growing demand for primary care."

American Ambassador to Israel Dan Shapiro says plans for a military strike on Iran's nuclear facilities are "fully available" and "ready."

In remarks aired by Israel's Army Radio on Thursday, Shapiro said: "It would be preferable to resolve this diplomatically and through the use of pressure than to use military force. But that doesn't mean that option is not fully available — not just available, but it's ready.

"The necessary planning has been done to ensure that it's ready."

Israel has hinted it could launch a pre-emptive attack on Iran's nuclear development program, which Iran insists is for peaceful purposes but Israel believes is aimed at producing nuclear weapons.

However, many analysts believe the United States alone has the ability to inflict lasting damage on Iran's program, the Israeli newspaper Haaretz reported.

Award-winning journalist Arnaud de Borchgrave recently told Newsmax in an interview that a U.S. strike against Iran would be "the height of strategic madness" because it could escalate rapidly into a regional war.

But Israeli Defense Minister Ehud Barak recently asserted that a "radical Islamic Republic of Iran with nuclear weapons would be far more dangerous both for the region and, indeed, the world" than an attack on Iran.

Ambassador Shapiro's comments came days before the scheduled resumption of talks between Iran and Western allies in Baghdad.

The struggling U.S. economy has been particularly hard on young people — Americans ages 18 to 29 are suffering higher unemployment and underemployment rates than other age groups, a new Gallup poll reveals.

Unemployment among young adults stood at 13.6 percent in April, up from 12.5 percent in March and the same as in April 2011.

Among those ages 30 to 49, the unemployment rate stood at 7 percent in April, and at just 6.2 percent among those ages 50 to 64.

In addition to the unemployed, 18.4 percent of young Americans are working part time but looking for full-time work. Combining that figure with the 13.6 percent unemployed brings the underemployment total to 32 percent — essentially one-third of all Americans ages 18 to 29, according to Gallup.

That's up from 30.1 percent in March and 30.7 percent in April 2011, so their situation is not improving.

Underemployment in April was 14 percent among those ages 30 to 49, and 13.6 percent among those ages 50 to 64.

"April has brought gloomy job news for young Americans and underscores that this group has been struggling disproportionately for some time," Gallup observes.

Gallup points out that only 3.1 percent of young adults say they are self-employed, compared to 7.3 percent of all Americans in the workforce. Most young people lack the necessary experience and knowledge to succeed in self-employment.

"Nearly one in three young adults in the workforce are not now able to gain full-time job experience," Gallup concludes.

"This not only hurts them temporarily, but deprives them of the experience they need to get a better job in the future. It also deprives U.S. companies of the skilled and experienced workers they will need for their businesses to prosper in the years ahead."

Forbes magazine has released its new list of "The World's Most Powerful Celebrities," and singer-actress-entrepreneur Jennifer Lopez tops the list, replacing the previous list's top celeb, singer Lady Gaga.

Donald Trump and Rush Limbaugh are also high on the new list.

Forbes' "Celebrity 100" list — which includes film and television actors, TV personalities, models, athletes, authors, musicians, and comedians — is based on "money and fame," Forbes explains.

"We define fame as media visibility in print, television, radio, and online, plus social media power, which we measure by looking at each celebrity's presence on Facebook and Twitter.

"The earnings consist of pretax income between May 1, 2011, and May 1, 2012. Management, agent, and attorney fees are not deducted."

After several down years, Lopez rebounded in 2010 by landing a judge's chair on "American Idol," although there are reports she is leaving the show to devote more time to other endeavors.

"The job gave her a platform to promote her music and turn her image around," Forbes observed.

"It didn't hurt that she also split from her husband, Marc Anthony. Suddenly a single mother, Lopez lapped up the media attention and scored lucrative endorsement deals with companies like L'Oreal and Gillette. She now has a line of clothing at Kohl's and a top-selling fragrance.

"With 6.6 million followers on Twitter and 12 million fans on Facebook, she's also proved a master of social media."

Lopez reportedly earned $52 million during the year.

In second place on the list is Oprah Winfrey, whom Lady Gaga unseated for No. 1 last year. Winfrey was the top earner on the list, bringing in $165 million thanks in part to her of spin-off shows including "Dr. Phil."